Gov. Code, § 20691

(a) (1) Except as provided in subdivision (b), notwithstanding any other law, a contracting agency or school employer may pay all or a portion of the normal contributions required to be paid by a member. Where the member is included in a group or class of employment, the payment shall be for all members in the group or class of employment. If an individual is not part of a group or class, the payment shall be limited to the amount that the board determines is payable to similarly situated members in the closest related group or class, subject to the limitations of paragraph (2) of subdivision (e) of Section 20636 and paragraph (2) of subdivision (e) of Section 20636.1, as applicable. The payments shall be reported simply as normal contributions and shall be credited to member accounts.

(2) Nothing in this subdivision shall be construed to limit the authority of a contracting agency or school employer to periodically increase, reduce, or eliminate the payment by the contracting agency or school employer of all or a portion of the normal contributions required to be paid by members, as authorized by this section.

(b) Notwithstanding subdivision (a), employers shall not pay a portion of the normal contributions for members who are subject to subdivision (c) of Section 7522.30, except where authorized pursuant to subdivision (f) of Section 7522.30.